Method and apparatus for controlling shearing of metallic workpieces

ABSTRACT

This disclosure relates to the art of producing predetermined length cuts of steel billets by a flying shear. It includes a primary pinch roll machine arranged in front of the shear to advance all but the trailing end portion of the billet to the shear for cutting into desired lengths. Between the primary pinch roll machine and the shear and immediately adjacent the shear, there is arranged a secondary pinch roll machine. A measuring roll is provided to measure the length of the billet, except for the trailing end thereof issuing to the shear. This measuring operation is employed to control the operation of the shear in cutting the billet into a number of desired length cuts. The trailing end portion of the billet is not measured by the measuring roll but instead by the second pinch roll machine, which also advances the trailing end portion to the shear.

[451 June 20, 1972 United States Patent Contaldo et al.

83/364 X ....83/364 X 83/364 X y 1 NW mww www Man 850 xum an 333 R ma m w We m m n n R A DNW NI A C I OL mun TNT E E MCM [7 2] Inventors: Joseph Contaldo, Sewickley; George Primary Examiner1ames M. Meister Pripeton, Boyers, both of Pa. Attorney-Henry C. Westin ABSTRACT This disclosure relates to the art of producing predetermined [73] Assignee: United Engineering and Foundry Company, Pittsburgh, Pa.

Nov. 12, 1969 [22] Filed:

length cuts of steel billets by a flying shear. It includes a prima- [21] APPL NOS 875,655 ry pinch roll machine arranged in front of the shear to advance all but the trailing end portion of the billet to the shear for cutting into desired lengths. Between the primary pinch roll 8 except for the trailing end thereof issuing to the shear. This rne machine and the shear and immediately adjacent the shear, there is arranged a secondary pinch roll machine. A measurin roll is provided to measure the length of the billet,

asuring operation is employed to control the operation of the shear in cutting the billet into a number of desired length cuts. The trailing end portion of the billet is not measured by the measuring roll but instead by the second pinch roll machine, which also advances the trailing end portion to the shear.

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UNITED STATES PATENTS 2,728,040 Hunt, Jr. et al. ....................83/295 X 5 Claims, 4 Drawing Figures PATENTEDJum I972 3, 670 609 sum 1 0F 5 INVENTORS. JOSEPH CONT/11.00 BY GEO GE PR/PETON a M dm A TTORNE Y.

P'A'TENTEnJunzo I972 3. 670,609

saw ear 3 INVENTORS.

JOSEPH colvmLoo BY GEORGE PR/PETOA/ a/m am ATTORNEY.

METHOD AND APPARATUS FOR CONTROLLING SI-IEARING F METALLIC WORKPIECES Modern steel plants strive not only to reduce the scrap losses in the rolling process but to optimize the shearing of the product to obtain the maximum amount of salable lengths of a given hot rolled product, such as a billet and the like. In producing, for example, carbon steel billets, the finally rolled billet is sheared into predetermined lengths immediately after leaving thelast stand of the mill. The front and back of the billet is chopped off as scrapso that the remaining portion of the billet presents prime material. In order to obtain a maximum number of predetermined length cuts, it is important to have a procedure for accurately measuring the total length of the billet as it issues to the shear including the trailing end portion. In addition to having a procedure whereby in cropping the front and back ends care is taken not to excessively crop so as to jeopardize obtaining the maximum number of predetermined length cuts, consideration must also be given to the fact that the pinch roll normally employed to advance the billet to the shear, because of its size, cannot be mounted closely adjacent the shear so that, with regard to the trailing end portion, a problem exists in measuring and driving this portion of the billet.

It is, therefore, the object of the present invention to provide a method and apparatus and control for operating a flying shear in a manner to optimize the number of length cuts of a given length rolled workpiece.

It is a further object of the present invention to provide primary and auxiliary pinch roll driving units adapted to advance the workpiece to the shear in a manner that a maximum number of length cuts for a given length workpiece can be obtained.

It is a further object of the present invention to provide in combination with dual pinch roll units a measuring roll to measure the actual length of the workpieces issuing to the shear, except for the trailing end portion thereof, and means to permit the auxiliary pinch roll unit to be employed to both advance the trailing end portion of the workpiece and measure this portion as it issues to the shear.

It is another object of the present invention to provide an auxiliary pinch roll for advancing a workpiece to a shear or like device which will allow itself to be mounted closely adjacent the cutting zone of the shear and operate in an area close to the cutting zone.

These objects, as well as other features and advantages of the present invention, will be better appreciated when the following specification is read in light of the accompanying drawings, of which:

FIG. 1 is an elevational view of a shear and of a primary and auxiliary pinch roll unit following the teaching of the present invention;

FIG. 2 is a plan view of the apparatus illustrated in FIG. 1;

FIG. 3 is a partial sectional view taken on lines IIIIII of FIG. 2; and

FIG. 4 is a schematic electrical diagram of the shear control employed with respect to the shear illustrated in FIGS. 1 and 2 In referring to FIG. 1, there is illustrated a conventional flying shear designed to sever carbon steel billets, measuring between 2% X 2% inch to 5 X 5 inch, that issue from a rolling mill in a direction indicated by the arrow at the left-hand side of the figure. The shear follows generally conventional designs, as typified, for example, in U.S. Pat. No. 2,878.869, and consists of two spaced-apart cranks l2 and 13 which are geared together by gearing, not shown, and which rotate knifeheads 14 and 15 in a circular path in the direction represented by the arrows in FIG. 1, so as to advance into a cutting position knives 16 and 17. The positions of the knives in FIG. 1 represent their closed positions, which they assume upon completion of the severing of the workpiece. The paths of the knives, according to customary designs, are controlled by identical arrns 18 and 19 which are pivotally mounted on secondary arms 21 and 22, the secondary arms being supported by shafts 23 and 24 which are rotatably carried by the.

housing of the shear.

It should be noted that the shear illustrated is a continuously operating shear wherein the speed of the knives l6 and 17 will be synchronized with the constant speed of the billet during the cutting phase.

To the left of FIG. 1 there is illustrated what is referred to in the specification as the primary pinch roll unit which consists of two identical rolls 25 and 26 designed, as shown in FIG. 2, to have a V formed in their bodies so as to fit the cross-section of the billet issuing to the pinch rolls in which the contact allows the pinch rolls to drive the billet to the shear for shearing. Since the roll assemblies consist of identical components, it is deemed necessary to describe only the upper roll 25. As shown in FIG. 2, it is cantilever-mounted by two parallel levers or arms 28 which are pivotally supported by a shaft 29 which extends out from the shear housing in a cantilever fashion so that its inward end is supported by the housing of the shear proper. The actual support of the shaft 29 is provided by a vertical plate 31 which extends away from the housing of the shear, and provides a space between the housing and the end of the shaft 29. As best seen in FIG. 3, between the housing and the support plate 31 there are provided equalizing segmental gears 32 and 33 which tie together the two pinch rolls 25 and 26 so as to assure equal vertical displacement thereof. This displacement is effected by cylinders 34 and 35 which are connected to the extensions of the shafts 29 by arms 36 and 37.

Inward of the primary pinch rolls 25 and 26 and closely adjacent to the shearing zone of the shear knives 16 and 17 there is provided a secondary or auxiliary pinch roll unit. This unit consists of identical top and bottom rolls 41 and 42, for which reason only the roll 41 and its related parts will be described. As shown in FIG. 2, the roll 41 has its body section in the form of a V" to conform with the crosssection of the billet issuing to the shear. It likewise is cantilever-mounted having its inner end rotatably supported by a plate 43 which is spaced outward of the plate 31 which supports the shafts 29 of the primary pinch rolls. The plate 43 is pivotally connected to the shear housing by an outwardly extending pin 44 which allows the plate, and hence the rolls as a unit, to move vertically. Movement of the rolls independent of the plate 43 is accomplished in the case of the roll 41 by a piston cylinder assembly 45 which is connected to the plate through a link 46 and, by virtue of a pin 47, the link is connected to an arm 48 that carries the pinch roll 41. The pin 47 actually is received in a slot in the plate 43, as can be seen in referring to FIG. 3, which allows the pin to move relative to the plate upon operation of the cylinders 45. The upper pinch roll 41 outward of its bearings is connected to a piston cylinder assembly 51 employed to apply a downward pressure so as to pinch the billet between two rolls 41 and 42 and provide sufficient friction to drive the billet to the shear.

As mentioned previously, the entire assembly is pivotable about the pin 44 and, for this purpose, there is provided a piston cylinder assembly 52 connected to the plate 43 by an ear 53, the piston cylinder assembly 52 acting as a balance which allows the entire auxiliary pinch roll assembly to move upwardly during the shearing action when the billet is raised by the lower knife 17 of the shear. In this regard, the cylinder 52 urges the plate downward so that a projection 54 connected to the plate engages a stop 55 mounted on the shear housing, the stop being shown best in FIG. 1.

In referring now to FIG. 2, it will be seen that the primary pinch rolls 25 and 26 are each driven by a motor gear unit 56 through spindles 57, only the spindle for the upper roll being shown. The auxiliary pinch rolls 41 and 42 are similarly driven by a motor gear assembly 58 through spindles 60, in which regard only the spindle for the upper roll 41 is shown. In addition, and in still referring to FIG. 2, the drive component of the auxiliary pinch rolls consists of a pulse generator 61 which, in a usual fashion, will measure the rotation of the auxiliary pinch rolls 41 and 42 which will represent a measurement of the length of the billet issuing through the pinch roll.

In referring now to FIG. 4, which represents a schematic electrical diagram of the shear control, it will first be noted that there is illustrated the last stand of the billet mill 62. Proceeding from left to right, there is located in the path of the billet a heat detector 63, a measuring roll 64, followed by the primary pinch rolls 25 and 26 and the secondary pinch rolls 41 and 42, after which comes the shear 10, The measuring roll 64 is connected to a drive and control system which produces a signal of the length of billet issuing over the roll which is fed to a main control 65. The primary pinch rolls, likewise, are associated with a drive and tachometer generator which feeds a signal to the main control 65. This signal represents the speed of the billet issuing from the primary pinch rolls. In a similar manner, the auxiliary pinch rolls are connected to a drive and pulse generator system which feeds a signal to the main control 65 representing a measurement of the material issuing from the auxiliary pinch rolls. In addition, a signal representing the desired length cut and a signal representing the crop data is fed to the main control which then produces a signal for the shear drive itself to control the cycling of the shear, both with respect to the desired length cuts and to the amount of crop to be taken from the front and back of the billet.

The following is a brief explanation of the operation of the aforesaid arrangement. As noted previously, the primary object is to optimize the shearing of the product so that the maximum number of length cuts can be obtained and wherein the end cropping is done in a manner so as not to jeopardize this goal. For example, if the measured length of the billet issued from the mill 60 is 483 ft. and it is desired to cut l6-ft. lengths, the 3 ft. left over represent what is available for cropping if exactly 30 lengths are to be sheared at 16 ft. per length.

It should also be appreciated that an estimation of the total length is generally known prior to rolling so that the operator knows approximately how many length cuts of a desired length a given billet will produce. He does not, however, know how much he can crop off the front and back ends without inadvertently leaving a piece of prime material of a length less than the desired length.

In referring to FIG. 4, the billet is measured prior to entering the mill 62 by a procedure that will give its total length prior to rolling. In addition to this, the amount of elongation by rolling is measured, which is added to the previously measured length to arrive at the final length of the billet issuing from the mill to the shear, and a signal for which is fed to the shear main control 65. Also fed to the main control is a signal of the exact length of billet issuing to the shear as measured by the measuring roll 64. At the same time, the peripheral speed of the billet is measured by the primary pinch rolls 25 and 26, the signal for which is sent to the main control. From the signals of the measured values, the control computes what is available for cropping and a signal representing the data is fed to the main control. After the leading end crop is sheared, the shear is operated by the control to cut the bar into the desired length cuts, in which case each length thereof is measured by the measuring roll 64. During this period, the billet is advanced to the shear by the primary pinch rolls 25 and 26. As the trailing end leaves the mill 62, its presence is detected by a heat detector 63 which sends a signal to the main control 65 to disengage the primary pinch rolls 25 and 26 and engage the auxiliary pinch rolls 41 and 42, At that point, the pinch rolls 41 and 42 through the pulse generator 69 begin to measure the billet issuing to the shear 10 in the same fashion that the measuring roll 64 did. Since the auxiliary pinch rolls are mounted in close proximity to the cutting zone of the shear, they minimize the amount of unmeasured material going to the shear and, therefore, allow the operator to measure almost the entire length of the billet. After the last desired length has been cut, the piece that remains represents the difierence between what was cropped off the front end of the billet and what was initially determined to be available for both front and back cropping.

In accordance with the provisions of the patent statutes, we have explained the principle and operation of our invention and have illustrated and described that we consider to represent the best embodiment thereof.

We claim:

1. In an apparatus for advancing a workpiece to a shearing device, comprising:

a primary driving unit for advancing the workpiece to said shearing device,

an auxiliary driving unit arranged between said primary driving unit and said shearing device and adjacent to the cutting zone of said shearing device,

means for causing said primary driving unit to advance all but the trailing end of said portion of the workpiece towards said shearing device, and

means for causing an auxiliary driving unit to advance only the trailing end of the workpiece towards said shear.

2. An apparatus according to claim 1 wherein said primary driving device comprises a pair of pinch rolls arranged on opposite sides of the path of travel of the workpiece,

said pinch rolls carried by arms,

said arms extending away from said pinch rolls and toward said shearing device,

means for pivotally carrying said arms in a manner that the pinch roll can move towards and away from said path of travel,

separate piston cylinder assemblies connected to said arms to effect said movement of said pinch rolls, and

means mounted on said carrying means for equalizing the displacement of said pinch rolls.

3. An apparatus according to claim 1 wherein said auxiliary driving unit comprises,

a pair of pinch rolls arranged on opposite sides of the path of travel of the workpiece and including means for urging one of said pinch rolls towards the other to cause said pinch rolls to assume a driving relationship with the workpiece.

4. In combination with a shearing device for shearing elongated workpieces and a primary driving unit and an auxiliary driving unit arranged between said primary driving unit and said shearing device and immediately adjacent said shearing device,

a control system comprising means for causing said primary driving device to engage all but the trailing end portion of the workpiece and advance it to the shearing device,

means for producing a signal representing the length of the workpiece being advanced by said primary driving device,

means for receiving said signal and controlling the operation of said shearing device to shear said workpiece into one or more predetermined lengths,

means for interrupting engagement of the workpiece by said primary driving device and for engaging the trailing end portion of the workpiece by said auxiliary driving device,

means for producing a second signal representing the length of the workpiece being advanced by said auxiliary driving unit, and

means for receiving said second signal and controlling the said shearing device to shear said trailing end portion into one or more predetermined length cuts,

5. In a method of advancing an elongated workpiece to a shearing device for shearing into predetermined lengths and employing a primary workpiece driving unit and an auxiliary workpiece driving unit arranged between said primary driving unit and said shearing device and adjacent the cutting zone of said shearing device, the steps comprising:

causing the primary driving unit to advance all but the trailing end portion of the workpiece to the shearing device,

producing a signal representing the measurement of that portion of the workpiece excluding the trailing end portion thereof,

using said first signal to produce a shear control for causing said shearing device to out said portion in the desired length cuts,

producing a third signal representing the location of the trailing end portion of said workpiece with reference to a given reference point along the path of travel of the workpiece,

the trailing end portion of said workpiece, and

i using said fourth signal to produce a shear control signal for causing said shearing device to cut said trailing end pot tion into desired length cuts 

1. In an apparatus for advancing a workpiece to a shearing device, comprising: a primary driving unit for advancing the workpiece to said shearing device, an auxiliary driving unit arranged between said primary driving unit and said shearing device and adjacent to the cutting zone of said shearing device, means for causing said primary driving unit to advance all but the trailing end of said portion of the workpiece towards said shearing device, and means for causing an auxiliary driving unit to advance only the trailing end of the workpiece towards said shear.
 2. An apparatus according to claim 1 wherein said primary driving device comprises a pair of pinch rolls arranged on opposite sides of the path of travel of the workpiece, said pinch rolls carried by arms, said arms extending away from said pinch rolls and toward said shearing device, means for pivotally carrying said arms in a manner that the pinch roll can move towards and away from said path of travel, separate piston cylinder assemblies connected to said arms to effect said movement of said pinch rolls, and means mounted on said carrying means for equalizing the displacement of said pinch rolls.
 3. An apparatus according to claim 1 wherein said auxiliary driving unit comprises, a pair of pinch rolls arranged on opposite sides of the path of travel of the worKpiece and including means for urging one of said pinch rolls towards the other to cause said pinch rolls to assume a driving relationship with the workpiece.
 4. In combination with a shearing device for shearing elongated workpieces and a primary driving unit and an auxiliary driving unit arranged between said primary driving unit and said shearing device and immediately adjacent said shearing device, a control system comprising means for causing said primary driving device to engage all but the trailing end portion of the workpiece and advance it to the shearing device, means for producing a signal representing the length of the workpiece being advanced by said primary driving device, means for receiving said signal and controlling the operation of said shearing device to shear said workpiece into one or more predetermined lengths, means for interrupting engagement of the workpiece by said primary driving device and for engaging the trailing end portion of the workpiece by said auxiliary driving device, means for producing a second signal representing the length of the workpiece being advanced by said auxiliary driving unit, and means for receiving said second signal and controlling the operation of said shearing device to shear said trailing end portion into one or more predetermined length cuts.
 5. In a method of advancing an elongated workpiece to a shearing device for shearing into predetermined lengths and employing a primary workpiece driving unit and an auxiliary workpiece driving unit arranged between said primary driving unit and said shearing device and adjacent the cutting zone of said shearing device, the steps comprising: causing the primary driving unit to advance all but the trailing end portion of the workpiece to the shearing device, producing a signal representing the measurement of that portion of the workpiece excluding the trailing end portion thereof, using said first signal to produce a shear control for causing said shearing device to cut said portion in the desired length cuts, producing a third signal representing the location of the trailing end portion of said workpiece with reference to a given reference point along the path of travel of the workpiece, employing said third signal to interrupt the driving effect of said primary driving unit and to cause said auxiliary driving unit to advance the trailing end portion of the workpiece to said shearing device, using the driving motion of said auxiliary driving unit to produce the fourth signal representing a measurement of the trailing end portion of said workpiece, and using said fourth signal to produce a shear control signal for causing said shearing device to cut said trailing end portion into desired length cuts. 